Some ingenious persons might have started shaping clay into the forms of various animals, insects, and so on, including something shaped like a tortoise shell, which were in use at the time. Others, remembering that clay hardens in fire, might have fired the hollowed-out mass, thereby creating the first bowl.
After that, it was a relatively easy matter to perfect the new invention; someone else could discover a clay more suitable for such manufactures; someone else could invent a glaze, and so on, with nature and observation at every step pointing out to man the way to invention. If the people had not observed that clay hardens in fire, if they had not observed that water lingers longer inside a depression, if one of them had not wanted to form clay into something shaped like a tortoise shell, the first clay bowl would not have been invented.
What I have said may not necessarily have taken place, but it is not improbable and illustrates how people arrive at various ideas: by closely observing all things and wondering about all things.
Take another example. We know that sometimes, in a pane of glass, we find disks and bubbles, looking through which we see objects more distinctly than with the naked eye. Suppose that an observant person, spotting such a bubble in a pane, removed the piece of glass and showed it to others as a toy. Possibly among them there was a man with weak vision who found that, through the bubble in the pane, he saw better than with the naked eye. Further investigation showed that bilaterally convex glass strengthens weakened vision, and in this way eyeglasses were invented. Initially people may have cut glass for eyeglasses from glass panes,
